gc: avoid package name ambiguity in error messages

Fixes issue 2006.

R=ken2
CC=golang-dev
http://codereview.appspot.com/4643056

3 files changed, 50 insertions, 0 deletions

diff --git a/test/fixedbugs/bug345.dir/io.go b/test/fixedbugs/bug345.dir/io.go
new file mode 100644
index 000000000..1d695c304
--- /dev/null
+++ b/test/fixedbugs/bug345.dir/io.go
@@ -0,0 +1,15 @@
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package io
+
+type Writer interface {
+	WrongWrite()
+}
+
+type SectionReader struct {
+	X int
+}
+
+func SR(*SectionReader) {}
diff --git a/test/fixedbugs/bug345.dir/main.go b/test/fixedbugs/bug345.dir/main.go
new file mode 100644
index 000000000..5bdc713f4
--- /dev/null
+++ b/test/fixedbugs/bug345.dir/main.go
@@ -0,0 +1,28 @@
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package main
+
+import (
+	"bufio"
+	"./io"
+	goio "io"
+)
+
+func main() {
+	// The errors here complain that io.X != io.X
+	// for different values of io so they should be
+	// showing the full import path, which for the
+	// "./io" import is really ..../go/test/io.
+	// For example:
+	//
+	// main.go:25: cannot use w (type "/Users/rsc/g/go/test/fixedbugs/bug345.dir/io".Writer) as type "io".Writer in function argument:
+	//	io.Writer does not implement io.Writer (missing Write method)
+	// main.go:27: cannot use &x (type *"io".SectionReader) as type *"/Users/rsc/g/go/test/fixedbugs/bug345.dir/io".SectionReader in function argument
+
+	var w io.Writer
+	bufio.NewWriter(w)  // ERROR "test/io"
+	var x goio.SectionReader
+	io.SR(&x)  // ERROR "test/io"
+}
diff --git a/test/fixedbugs/bug345.go b/test/fixedbugs/bug345.go
new file mode 100644
index 000000000..874710ce8
--- /dev/null
+++ b/test/fixedbugs/bug345.go
@@ -0,0 +1,7 @@
+// $G $D/$F.dir/io.go && errchk $G -e $D/$F.dir/main.go
+
+// Copyright 2011 The Go Authors.  All rights reserved.
+// Use of this source code is governed by a BSD-style
+// license that can be found in the LICENSE file.
+
+package ignored